This image released by Netflix shows Kevin Spacey as Francis Underwood, left, and Robin Wright as Clair Underwood in a scene from "House of Cards." The second season of the popular original series premieres on Friday, Feb. 14, 2014 on Netflix.

Binge-Watch 'House of Cards' on Valentine's Day at Your Own Risk

By Keith Wagstaff

Kevin Spacey's slick Southern statesman in House of Cards may not be much of a romantic, but plenty of singles and couples home on Valentine's Day may spend their time watching episode after episode packed with his political machinations.

Yes, Netflix’s Emmy-award winning drama is back for a second season, and plenty of viewers are expected to indulge in the new American tradition of binge-watching. That could include former President Bill Clinton, who reportedly watched the first season in only three days. (Coincidentally, the show’s star, Kevin Spacey, plays a slick Democratic politician from the South who rises to power in Washington).

Clinton isn’t the only one binging. In December, Netflix released a study that looked at how people watched 10 of its popular shows. For one drama, 25 percent of users finished an entire 13-episode series in only two days.

On "Portlandia," "Saturday Night Live" alum Fred Armisen and former Sleater Kinney member Carrie Brownstein ruin their lives by binging on "Battlestar Galactica."

But will binge-watching TV really frak up your mind? Not really, but it's best not to overdo it, says John Black, a professor at the Teacher’s College at Columbia University who studies how technology affects learning and memory. He compared the experience to getting hooked on drugs.

“You take a dosage of a drug and have a certain amount of reaction to it,” Black told NBC News. “But if you keep doing it, it takes more and more of the same drug to get the same reaction. If you’re watching too much at a time, you kind of get dull to it and you’re not really appreciating the show.”

The same is true of any activity that releases endorphins and leads us to relax and feel pleasure. Netflix, however, just makes it easy to keep feeding that addiction by automatically playing the next episode after one ends.

Black, however, is actually a fan of binge-watching in moderation. He admitted to watching entire seasons of the AMC drama "Breaking Bad" — an addictive show that, appropriately enough, centers around the meth trade. The key is to watch in stretches long enough so that you can appreciate the intricate storylines, but not so long enough that you zone out.

"If you’re watching too much at a time, you kind of get dull to it and you’re not really appreciating the show."

But, aside from wasting time that could otherwise be spent volunteering or writing the great American novel, you aren’t really doing long-lasting damage to your brain, he said.

That doesn’t mean that it’s healthy behavior. If binge-watching cuts into sleep time, that could have a serious effect on your mental health. And no, watching football players do laps on “Friday Night Lights” doesn’t count as physical exercise.

“There’s convincing evidence in adults that the more television people watch, the more likely they are to gain weight or become overweight or obese,” Lilian Cheung, a lecturer at the Harvard School of Public Health, wrote to NBC News in an email. “And there’s emerging evidence that too much TV watching also increases the risk of weight-related chronic diseases, such as Type 2 diabetes.”

Even worse: The negative effects of “sit time” aren’t mitigated by exercise, meaning that running a mile won’t undo the damage done to your body by watching the entire first season of “Walking Dead” on your couch.

On the plus side, binge-watching lets you skip fast-food commercials, Cheung wrote, which may be a major factor in the link between TV and obesity.

Yes, there is a healthier option on Valentine’s Day than watching Kevin Spacey speak in a faux-southern accent for 12 hours: getting busy.

You burn about three times as many calories having sex than you do while staring at your TV screen, according to a recent study published in the New England Journal of Medicine. The bad news? People only spend about six minutes on average doing the deed, meaning that you'll end up only burning around 21 calories. At least you will have something to watch when you're done.

First published February 14 2014, 6:29 AM

Keith Wagstaff

Keith Wagstaff is a contributing writer at NBC News. He covers technology, reporting on Internet security, mobile technology and more. He joined NBC News from The Week, where he was a staff writer covering politics. Prior to his work at The Week, he was a technology writer at TIME.